Associations between modifiable risk factors and white matter of the aging brain: insights from diffusion tensor imaging studies

Abstract

There is increasing interest in factors that may modulate white matter (WM) breakdown and, consequentially, age-related cognitive and behavioral deficits. Recent diffusion tensor imaging studies have examined the relationship of such factors with WM microstructure. This review summarizes the evidence regarding the relationship between WM microstructure and recognized modifiable factors, including hearing loss, hypertension, diabetes, obesity, smoking, depressive symptoms, physical (in) activity, and social isolation, as well as sleep disturbances, diet, cognitive training, and meditation. Current cross-sectional evidence suggests a clear link between loss of WM integrity (lower fractional anisotropy and higher mean diffusivity) and hypertension, obesity, diabetes, and smoking; a relationship that seems to hold for hearing loss, social isolation, depressive symptoms, and sleep disturbances. Physical activity, cognitive training, diet, and meditation, on the other hand, may protect WM with aging. Preliminary evidence from cross-sectional studies of treated risk factors suggests that modification of factors could slow down negative effects on WM microstructure. Careful intervention studies are needed for this literature to contribute to public health initiatives going forward.

Association between ambulatory blood pressure variability and frailty among older hypertensive patients

“…In line with previous studies, we observed the strong association between ageing and frailty status 35,36 . Aging is the accumulation of changes responsible for the advanced disease and adverse outcomes including cognitive decline, falls, and death, 37,38 which could explain the facts that elderly individuals who accumulate more deficits and undergo more adverse events tend to be frailer as age increases.…”

Cardiorespiratory fitness diminishes the effects of age on white matter hyperintensity volume

“…However, little is known about the effects of CRF on WMH volume per se. In contrast, higher CRF has been linked to higher WM microstructure in older adults [26][27][28]. Since low WM microstructure in normal appearing WM precedes conversion to WMHs [29,30], WMHs may also be positively influenced by high CRF [31][32][33].…”

Mid-life and late life activities and their relationship with MRI measures of brain structure and functional connectivity in the UK Biobank cohort

“…Leisure activities have been systematically linked to better cognitive performance and structural brain integrity in older adults [5][6][7][8][9][10][11][12][13]. However, one of the major drawbacks of published studies is the longstanding use of composite measures of leisure activities, which provides limited insight into the specific activities that should be targeted by interventions to promote brain health in older individuals.…”